Our objective is to expand current information on the nature of human tear proteins and compare the ability of the lacrimal gland to respond in volume and variation of tear composition in basal tears and during reflex tearing in normals, normals on autonomic drugs, keratoconjunctivitis sicca (KCS), patients with dry mouths and decreased salivary flow, patients with Sjogren's syndrome, hypothyroidism, and soft contact lens (CL) wearers who do not form deposits comparing with those who do form deposits. Tear volumes will be collected by our technique for basal and reflex tear sampling and KCS will be diagnosed by tear osmolarity. Tear samples will be collected from the inferior marginal tear strip and cul de sac with paper strips 2 x 16 mm (PeriopaperR) over a five second period and with Schirmer tear test strips over a five minute period. Tear volumes in the filter paper strips will be measured by means of an electronic resistance measuring device (PeriotronR) and millimeters length of wetting. Tear samples eluted from the filter paper strips will be analyzed for lysozyme and lactoferrin by rocket immunoelectrophoresis using specific antiserum. Tear samples will also be collected with capillary pipettes and albumin, immunoglobulins and phosphoproteins will be measured using recently developed chemical methods. Calcium and phosphate, both free and protein bound will be measured in tears of selected patients. Prospective studies will be carried out in cataract and lid surgery patients, glaucoma patients and soft contact lens wearers. Variation in tear composition as a result of different stimuli will also be examined.